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1.
Sci Immunol ; 9(94): eadi8039, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38579013

RESUMO

Vaccine adjuvants increase the breadth of serum antibody responses, but whether this is due to the generation of antigen-specific B cell clones with distinct specificities or the maturation of memory B cell clones that produce broadly cross-reactive antibodies is unknown. Here, we longitudinally analyzed immune responses in healthy adults after two-dose vaccination with either a virus-like particle COVID-19 vaccine (CoVLP), CoVLP adjuvanted with AS03 (CoVLP+AS03), or a messenger RNA vaccination (mRNA-1273). CoVLP+AS03 enhanced the magnitude and durability of circulating antibodies and antigen-specific CD4+ T cell and memory B cell responses. Antigen-specific CD4+ T cells in the CoVLP+AS03 group at day 42 correlated with antigen-specific memory B cells at 6 months. CoVLP+AS03 induced memory B cell responses, which accumulated somatic hypermutations over 6 months, resulting in enhanced neutralization breadth of monoclonal antibodies. Furthermore, the fraction of broadly neutralizing antibodies encoded by memory B cells increased between day 42 and 6 months. These results indicate that AS03 enhances the antigenic breadth of B cell memory at the clonal level and induces progressive maturation of the B cell response.


Assuntos
COVID-19 , Vacinas contra Influenza , Influenza Humana , Polissorbatos , Esqualeno , alfa-Tocoferol , Adulto , Humanos , Células B de Memória , Vacinas contra COVID-19 , Anticorpos Antivirais , COVID-19/prevenção & controle , Combinação de Medicamentos
2.
BMC Biotechnol ; 24(1): 13, 2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38459479

RESUMO

OBJECTIVE: Smoking was a major risk factor for chronic obstructive pulmonary disease (COPD). This study plan to explore the mechanism of Polyphyllin B in lung injury induced by cigarette smoke (CSE) in COPD. METHODS: Network pharmacology and molecular docking were applied to analyze the potential binding targets for Polyphyllin B and COPD. Commercial unfiltered CSE and LPS were used to construct BEAS-2B cell injury in vitro and COPD mouse models in vivo, respectively, which were treated with Polyphyllin B or fecal microbiota transplantation (FMT). CCK8, LDH and calcein-AM were used to detect the cell proliferation, LDH level and labile iron pool. Lung histopathology, Fe3+ deposition and mitochondrial morphology were observed by hematoxylin-eosin, Prussian blue staining and transmission electron microscope, respectively. ELISA was used to measure inflammation and oxidative stress levels in cells and lung tissues. Immunohistochemistry and immunofluorescence were applied to analyze the 4-HNE, LC3 and Ferritin expression. RT-qPCR was used to detect the expression of FcRn, pIgR, STAT3 and NCOA4. Western blot was used to detect the expression of Ferritin, p-STAT3/STAT3, NCOA4, GPX4, TLR2, TLR4 and P65 proteins. 16S rRNA gene sequencing was applied to detect the gut microbiota. RESULTS: Polyphyllin B had a good binding affinity with STAT3 protein, which as a target gene in COPD. Polyphyllin B inhibited CS-induced oxidative stress, inflammation, mitochondrial damage, and ferritinophagy in COPD mice. 16S rRNA sequencing and FMT confirmed that Akkermansia and Escherichia_Shigella might be the potential microbiota for Polyphyllin B and FMT to improve CSE and LPS-induced COPD, which were exhausted by the antibiotics in C + L and C + L + P mice. CSE and LPS induced the decrease of cell viability and the ferritin and LC3 expression, and the increase of NCOA4 and p-STAT3 expression in BEAS-2B cells, which were inhibited by Polyphyllin B. Polyphyllin B promoted ferritin and LC3II/I expression, and inhibited p-STAT3 and NCOA4 expression in CSE + LPS-induced BEAS-2B cells. CONCLUSION: Polyphyllin B improved gut microbiota disorder and inhibited STAT3/NCOA4 pathway to ameliorate lung tissue injury in CSE and LPS-induced mice.


Assuntos
Fumar Cigarros , Microbioma Gastrointestinal , Lesão Pulmonar , Doença Pulmonar Obstrutiva Crônica , Animais , Camundongos , Linhagem Celular , Fumar Cigarros/efeitos adversos , Ferritinas/metabolismo , Inflamação/patologia , Lipopolissacarídeos/efeitos adversos , Pulmão , Lesão Pulmonar/complicações , Lesão Pulmonar/metabolismo , Lesão Pulmonar/patologia , Simulação de Acoplamento Molecular , Doença Pulmonar Obstrutiva Crônica/terapia , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , RNA Ribossômico 16S , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo
3.
New Phytol ; 242(2): 641-657, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38379453

RESUMO

Nitrate is the main source of nitrogen (N) available to plants and also is a signal that triggers complex regulation of transcriptional networks to modulate a wide variety of physiological and developmental responses in plants. How plants adapt to soil nitrate fluctuations is a complex process involving a fine-tuned response to nitrate provision and N starvation, the molecular mechanisms of which remain largely uncharted. Here, we report that the wheat transcription factor TaLBD41 interacts with the nitrate-inducible transcription factor TaNAC2 and is repressed by nitrate provision. Electrophoretic mobility shift assay and dual-luciferase system show that the TaLBD41-NAC2 interaction confers homeostatic coordination of nitrate uptake, reduction, and assimilation by competitively binding to TaNRT2.1, TaNR1.2, and TaNADH-GOGAT. Knockdown of TaLBD41 expression enhances N uptake and assimilation, increases spike number, grain yield, and nitrogen harvest index under different N supply conditions. We also identified an elite haplotype of TaLBD41-2B associated with increased spike number and grain yield. Our study uncovers a novel mechanism underlying the interaction between two transcription factors in mediating wheat adaptation to nitrate availability by antagonistically regulating nitrate uptake and assimilation, providing a potential target for designing varieties with efficient N use in wheat (Triticum aestivum).


Assuntos
Nitratos , Nitrogênio , Nitratos/metabolismo , Nitrogênio/metabolismo , Transporte Biológico , Grão Comestível/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
4.
Health Expect ; 27(1): e13990, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38367247

RESUMO

BACKGROUND: With the growing challenge of an aging population, addressing the needs of elderly individuals who face living difficulties and lack family support becomes increasingly difficult. Volunteer services are crucial in this context, yet their effectiveness is hindered by unclear service scopes and uncertain volunteer inclinations. AIM: To explore the role and specific preference of volunteers with nursing backgrounds in support of older adults living in the urban community. DESIGN, SETTING AND PARTICIPANTS: A descriptive qualitative study was conducted between September and October 2022. Twenty-three participants (hospital nurses [10], community nurses [4], nursing teachers [4] and nursing students [5]) were selected. Data analysis followed conventional content analysis. RESULTS: Nine major themes were identified based on interview data. Four themes described the service scope of nursing volunteers: (1) environment domain, (2) physiological domain, (3) psychosocial domain and (4) health-related behaviours domain. Another five themes highlighted the service inclination of these volunteers: (1) service frequency, (2) service duration per person/time, (3) service coverage, (4) service place and (5) service object. CONCLUSION: This study clarifies the service focus and scope of necessary support for volunteers, exploring the potential service capabilities of scarce volunteers to the greatest extent. Meanwhile, the results of this study also provide a foundation for stakeholders to fully exploit the synergy. The important findings of this study will help the government and relevant authorities better understand the service attributes of nursing volunteers, allowing them to develop detailed training plans and provide nursing volunteers with targeted support and assistance to meet the health expectations of urban community-living older adults in need. PATIENT OR PUBLIC CONTRIBUTION: Developing research questions, participation and conduct and provision and interpretation of evidence.


Assuntos
Voluntários , Idoso , Humanos , Pesquisa Qualitativa , Vida Independente
5.
Microbiol Spectr ; 12(1): e0186823, 2024 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-38018983

RESUMO

IMPORTANCE: The link between gut microbiota and diet is crucial in the development of non-alcoholic steatohepatitis (NASH). This study underscores the essential role of a healthy diet in preventing and treating NASH by reversing obesity, lipidemia, and gut microbiota dysbiosis. Moreover, the supplementation of functional food or drug to the diet can provide additional advantages by inhibiting hepatic inflammation through the modulation of the hepatic inflammasome signaling pathway and partially mediating the gut microbiota and lipopolysaccharide signaling pathway. This study highlights the importance of adopting healthy dietary habits in treating NASH and proposes that supplementing with ginger essential oil or obeticholic acid may offer additional benefits. Nonetheless, further clinical studies are necessary to validate these findings.


Assuntos
Microbioma Gastrointestinal , Hepatopatia Gordurosa não Alcoólica , Humanos , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Dieta Saudável , Dieta Hiperlipídica/efeitos adversos , Fígado/metabolismo
7.
Cell ; 186(21): 4632-4651.e23, 2023 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-37776858

RESUMO

The dynamics of immunity to infection in infants remain obscure. Here, we used a multi-omics approach to perform a longitudinal analysis of immunity to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in infants and young children by analyzing blood samples and weekly nasal swabs collected before, during, and after infection with Omicron and non-Omicron variants. Infection stimulated robust antibody titers that, unlike in adults, showed no sign of decay for up to 300 days. Infants mounted a robust mucosal immune response characterized by inflammatory cytokines, interferon (IFN) α, and T helper (Th) 17 and neutrophil markers (interleukin [IL]-17, IL-8, and CXCL1). The immune response in blood was characterized by upregulation of activation markers on innate cells, no inflammatory cytokines, but several chemokines and IFNα. The latter correlated with viral load and expression of interferon-stimulated genes (ISGs) in myeloid cells measured by single-cell multi-omics. Together, these data provide a snapshot of immunity to infection during the initial weeks and months of life.


Assuntos
COVID-19 , SARS-CoV-2 , Adulto , Criança , Lactente , Humanos , Pré-Escolar , SARS-CoV-2/metabolismo , Multiômica , Citocinas/metabolismo , Interferon-alfa , Imunidade nas Mucosas
8.
Sci Transl Med ; 15(695): eadg7404, 2023 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-37163615

RESUMO

The rapid emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants that evade immunity elicited by vaccination has placed an imperative on the development of countermeasures that provide broad protection against SARS-CoV-2 and related sarbecoviruses. Here, we identified extremely potent monoclonal antibodies (mAbs) that neutralized multiple sarbecoviruses from macaques vaccinated with AS03-adjuvanted monovalent subunit vaccines. Longitudinal analysis revealed progressive accumulation of somatic mutation in the immunoglobulin genes of antigen-specific memory B cells (MBCs) for at least 1 year after primary vaccination. Antibodies generated from these antigen-specific MBCs at 5 to 12 months after vaccination displayed greater potency and breadth relative to those identified at 1.4 months. Fifteen of the 338 (about 4.4%) antibodies isolated at 1.4 to 6 months after the primary vaccination showed potency against SARS-CoV-2 BA.1, despite the absence of serum BA.1 neutralization. 25F9 and 20A7 neutralized authentic clade 1 sarbecoviruses (SARS-CoV, WIV-1, SHC014, SARS-CoV-2 D614G, BA.1, and Pangolin-GD) and vesicular stomatitis virus-pseudotyped clade 3 sarbecoviruses (BtKY72 and PRD-0038). 20A7 and 27A12 showed potent neutralization against all SARS-CoV-2 variants and multiple Omicron sublineages, including BA.1, BA.2, BA.3, BA.4/5, BQ.1, BQ.1.1, and XBB. Crystallography studies revealed the molecular basis of broad and potent neutralization through targeting conserved sites within the RBD. Prophylactic protection of 25F9, 20A7, and 27A12 was confirmed in mice, and administration of 25F9 particularly provided complete protection against SARS-CoV-2, BA.1, SARS-CoV, and SHC014 challenge. These data underscore the extremely potent and broad activity of these mAbs against sarbecoviruses.


Assuntos
COVID-19 , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave , Animais , Humanos , Camundongos , Anticorpos Amplamente Neutralizantes , Vacinas contra COVID-19 , Macaca , SARS-CoV-2 , COVID-19/prevenção & controle , Imunização , Vacinação , Anticorpos Monoclonais , Anticorpos Antivirais , Anticorpos Neutralizantes
9.
Opt Express ; 31(7): 11239-11248, 2023 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-37155764

RESUMO

Stable propagation of multifilament arrays in transparent bulk media with adjustable separation distances between adjacent child filaments has always been desired for advanced manufacturing. Here, we report on the generation of an ionization-induced volume plasma grating (VPG) by the interaction of two batches of noncollinearly propagating arrays of multiple filaments (AMF). The VPG can externally arrange the propagation of the pulses along regular plasma waveguides via spatial reconstruction of electrical fields, which is compared with the self-formation of randomly distributed multiple filamentation originated from noises. The separation distances of filaments in VPG are controllable by readily changing the crossing angle of the excitation beams. In addition, an innovative method to efficiently fabricate multidimensional grating structures in transparent bulk media through laser modification using VPG was demonstrated.

10.
Nat Commun ; 14(1): 2149, 2023 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-37069151

RESUMO

While the rapid development of COVID-19 vaccines has been a scientific triumph, the need remains for a globally available vaccine that provides longer-lasting immunity against present and future SARS-CoV-2 variants of concern (VOCs). Here, we describe DCFHP, a ferritin-based, protein-nanoparticle vaccine candidate that, when formulated with aluminum hydroxide as the sole adjuvant (DCFHP-alum), elicits potent and durable neutralizing antisera in non-human primates against known VOCs, including Omicron BQ.1, as well as against SARS-CoV-1. Following a booster ~one year after the initial immunization, DCFHP-alum elicits a robust anamnestic response. To enable global accessibility, we generated a cell line that can enable production of thousands of vaccine doses per liter of cell culture and show that DCFHP-alum maintains potency for at least 14 days at temperatures exceeding standard room temperature. DCFHP-alum has potential as a once-yearly (or less frequent) booster vaccine, and as a primary vaccine for pediatric use including in infants.


Assuntos
COVID-19 , Geranium , Nanopartículas , Animais , Humanos , Vacinas contra COVID-19 , Ferritinas , COVID-19/prevenção & controle , SARS-CoV-2 , Soros Imunes , Primatas , Anticorpos Neutralizantes , Anticorpos Antivirais
11.
J Clin Invest ; 133(10)2023 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-36951954

RESUMO

BackgroundMaintaining durable immunity following vaccination represents a major challenge, but whether mRNA booster vaccination improves durability is unknown.MethodsWe measured antibody responses in 55 healthy adults, who received a booster dose of the Pfizer-BioNTech or Moderna vaccine against SARS-CoV-2 and calculated the half-life of the antibody titers. We also measured memory B and T cell responses in a subset of 28 participants. In 13 volunteers who received a second booster vaccine, we measured serum antibody titers and memory B and T cell responses.ResultsThe booster (third immunization) dose at 6 to 10 months increased the half-life of the serum-neutralizing antibody (nAb) titers to 76 days from 56 to 66 days after the primary 2-dose vaccination. A second booster dose (fourth immunization) a year after the primary vaccination further increased the half-life to 88 days. However, despite this modestly improved durability in nAb responses against the ancestral (WA.1) strain, there was a loss of neutralization capacity against the Omicron subvariants BA.2.75.2, BQ.1.1, and XBB.1.5 (48-, 71-, and 66-fold drop in titers, respectively, relative to the WA.1 strain). Although only 45% to 65% of participants demonstrated a detectable nAb titer against the newer variants after the booster (third dose), the response declined to below the detection limit in almost all individuals by 6 months. In contrast, booster vaccination induced antigen-specific memory B and T cells that persisted for at least 6 months.ConclusionThe durability of serum antibody responses improves only marginally following booster immunizations with the Pfizer-BioNTech or Moderna mRNA vaccines.


Assuntos
COVID-19 , Adulto , Humanos , COVID-19/prevenção & controle , SARS-CoV-2 , Vacinas contra COVID-19 , Vacinação , RNA Mensageiro , Imunidade , Anticorpos Antivirais , Anticorpos Neutralizantes
12.
medRxiv ; 2023 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-36778389

RESUMO

The dynamics of innate and adaptive immunity to infection in infants remain obscure. Here, we used a multi-omics approach to perform a longitudinal analysis of immunity to SARS-CoV-2 infection in infants and young children in the first weeks and months of life by analyzing blood samples collected before, during, and after infection with Omicron and Non-Omicron variants. Infection stimulated robust antibody titers that, unlike in adults, were stably maintained for >300 days. Antigen-specific memory B cell (MCB) responses were durable for 150 days but waned thereafter. Somatic hypermutation of V-genes in MCB accumulated progressively over 9 months. The innate response was characterized by upregulation of activation markers on blood innate cells, and a plasma cytokine profile distinct from that seen in adults, with no inflammatory cytokines, but an early and transient accumulation of chemokines (CXCL10, IL8, IL-18R1, CSF-1, CX3CL1), and type I IFN. The latter was strongly correlated with viral load, and expression of interferon-stimulated genes (ISGs) in myeloid cells measured by single-cell transcriptomics. Consistent with this, single-cell ATAC-seq revealed enhanced accessibility of chromatic loci targeted by interferon regulatory factors (IRFs) and reduced accessibility of AP-1 targeted loci, as well as traces of epigenetic imprinting in monocytes, during convalescence. Together, these data provide the first snapshot of immunity to infection during the initial weeks and months of life.

13.
Foods ; 12(2)2023 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-36673453

RESUMO

The processing quality of wheat is affected by seed storage substances, such as protein and starch. High-molecular-weight glutenin subunits (HMW-GSs) are the major components of wheat seed storage proteins (SSPs); they are also key determinators of wheat end-use quality. However, the effects of HMW-GSs absence on the expression of other storage substances and the regulation mechanism of HMW-GSs are still limited. Previously, a wheat transgenic line LH-11 with complete deletions of HMW-GSs was obtained through introducing an exogenous gene Glu-1Ebx to the wild-type cultivar Bobwhite by transgenic approach. In this study, comparative seed transcriptomics and proteomics of transgenic and non-transgenic lines at different seed developmental stages were carried out to explore the changes in genes and proteins and the underlying regulatory mechanism. Results revealed that a number of genes, including genes related to SSPs, carbohydrates metabolism, amino acids metabolism, transcription, translation, and protein process were differentially enriched. Seed storage proteins displayed differential expression patterns between the transgenic and non-transgenic line, a major rise in the expression levels of gliadins were observed at 21 and 28 days post anthesis (DPA) in the transgenic line. Changes in expressions of low-molecular-weight glutenins (LMW-GSs), avenin-like proteins (ALPs), lipid transfer proteins (LTPs), and protease inhibitors (PIs) were also observed. In addition, genes related to carbohydrate metabolism were differentially expressed, which probably leads to a difference in starch component and deposition. A list of gene categories participating in the accumulation of SSPs was proposed according to the transcriptome and proteome data. Six genes from the MYB and eight genes from the NAC transcription families are likely important regulators of HMW-GSs accumulation. This study will provide data support for understanding the regulatory network of wheat storage substances. The screened candidate genes can lay a foundation for further research on the regulation mechanism of HMW-GSs.

14.
bioRxiv ; 2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36711543

RESUMO

The rapid emergence of SARS-CoV-2 variants that evade immunity to vaccination has placed a global health imperative on the development of therapeutic countermeasures that provide broad protection against SARS-CoV-2 and related sarbecoviruses. Here, we identified extremely potent pan-sarbecovirus antibodies from non-human primates vaccinated with an AS03 adjuvanted subunit vaccine against SARS-CoV-2 that recognize conserved epitopes in the receptor binding domain (RBD) with femtomolar affinities. Longitudinal analysis revealed progressive accumulation of somatic mutation in the immunoglobulin genes of antigen-specific memory B cells for at least one year following primary vaccination. 514 monoclonal antibodies (mAbs) were generated from antigen-specific memory B cells. Antibodies isolated at 5 to 12 months following vaccination displayed greater potency and breadth, relative to those identified at 1.4 months. Notably, 15 out of 338 (∼4.4%) antibodies isolated at 1.4∼6 months after the primary vaccination showed extraordinary neutralization potency against SARS-CoV-2 omicron BA.1, despite the absence of BA.1 neutralization in serum. Two of them, 25F9 and 20A7, neutralized authentic clade Ia sarbecoviruses (SARS-CoV, WIV-1, SHC014) and clade Ib sarbecoviruses (SARS-CoV-2 D614G, SARS-CoV-2 BA.1, Pangolin-GD) with half-maximal inhibition concentrations of (0.85 ng/ml, 3 ng/ml, 6 ng/ml, 6 ng/ml, 42 ng/ml, 6 ng/ml) and (13 ng/ml, 2 ng/ml, 18 ng/ml, 9 ng/ml, 6 ng/ml, 345 ng/ml), respectively. Furthermore, 20A7 and 27A12 showed potent neutralization against all SARS-CoV-2 variants of concern and multiple Omicron sublineages, including BA.1, BA.2, BA.3, BA.4/5, BQ.1, BQ.1.1 and XBB variants. X-ray crystallography studies revealed the molecular basis of broad and potent neutralization through targeting conserved RBD sites. In vivo prophylactic protection of 25F9, 20A7 and 27A12 was confirmed in aged Balb/c mice. Notably, administration of 25F9 provided complete protection against SARS-CoV-2, SARS-CoV-2 BA.1, SARS-CoV, and SHC014 challenge, underscoring that these mAbs are promising pan-sarbecovirus therapeutic antibodies. One Sentence Summary: Extremely potent pan-sarbecovirus neutralizing antibodies.

15.
Eur J Immunol ; 53(2): e2250190, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36480793

RESUMO

T follicular helper (TFH ) cells play an essential role in promoting B cell responses and antibody affinity maturation in germinal centers (GC). A subset of memory CD4+ T cells expressing the chemokine receptor CXCR5 has been described in human blood as phenotypically and clonally related to GC TFH cells. However, the antigen specificity and relationship of these circulating TFH (cTFH ) cells with other memory CD4+ T cells remain poorly defined. Combining antigenic stimulation and T cell receptor (TCR) Vß sequencing, we found T cells specific to tetanus toxoid (TT), influenza vaccine (Flu), or Candida albicans (C.alb) in both cTFH and non-cTFH subsets, although with different frequencies and effector functions. Interestingly, cTFH and non-cTFH cells specific for C.alb or TT had a largely overlapping TCR Vß repertoire while the repertoire of Flu-specific cTFH and non-cTFH cells was distinct. Furthermore, Flu-specific but not C.alb-specific PD-1+ cTFH cells had a "GC TFH -like" phenotype, with overexpression of IL21, CXCL13, and BCL6. Longitudinal analysis of serial blood donations showed that Flu-specific cTFH and non-cTFH cells persisted as stable repertoires for years. Collectively, our study provides insights on the relationship of cTFH with non-cTFH cells and on the heterogeneity and persistence of antigen-specific human cTFH cells.


Assuntos
Células T Auxiliares Foliculares , Linfócitos T Auxiliares-Indutores , Humanos , Linfócitos B , Centro Germinativo , Receptores de Antígenos de Linfócitos T
16.
medRxiv ; 2022 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-36482977

RESUMO

Waning immunity to vaccination represents a major challenge in vaccinology. Whether booster vaccination improves the durability of immune responses is unknown. Here we show, using a cohort of 55 adult vaccinees who received the BNT162b2 (Pfizer-BioNTech) or mRNA-1273 (Moderna) vaccine against SARS-CoV-2, that a booster (i.e., 3 rd immunization) dose at 6 - 10 months increased the half-life of serum neutralizing antibody (nAb) titers to 76 days from 56 - 66 days estimated after the primary two-dose vaccination series. A second booster dose (i.e., 4 th immunization) more than a year after the primary vaccination increased the half-life further to 88 days. However, despite this modestly improved durability in nAb responses against the Wuhan strain, there was a loss in neutralization capacity against Omicron subvariants, especially the recently emerged variants, BA.2.75.2 and BQ.1.1 (35 and 50-fold drop in titers respectively, relative to the ancestral (WA.1) strain. While only 55 â€" 65% of participants demonstrated a detectable nAb titer against the newer variants after the booster (3 rd dose), the response declined to below the detection limit in almost all individuals by 6 months. Notably, even against BA.1 and BA.5, the titers declined rapidly in a third of the vaccinees and were below the detection limit at 6 months. In contrast, booster vaccination induced antigen-specific memory B and T cells that persisted for at least 6 months. Collectively, our data show that the durability of immune responses improves following subsequent booster immunizations; however, the emergence of immune evasive variants reduces the effectiveness of booster doses in preventing infection.

17.
Xenobiotica ; 52(7): 718-728, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36227237

RESUMO

Curcumin, the main bioactive component of turmeric, has a wild range of beneficial effects on central nervous diseases, including anti-Alzheimer's disease, antioxidant stress, and anti-inflammation. Currently, it has been demonstrated the anti-epileptic potential. However, curcumin has poor water solubility, high sensitivity to light and heat, and low absorption, which results in low bioavailability and greatly limits the clinical application of curcumin, as well as the elusive effects in anti-epileptic treatment.This study aimed to develop a curcumin hydroxypropyl-ß-cyclodextrin inclusion complex (CUR-HP-ß-CD) to improve its bioavailability and facilitate its potential development as an anti-epileptic drug. The CUR-HP-ß-CD was generated by the solvent evaporation method, which has efficient entrapment, high solubility, and facilitated bioavailability and brain distribution.The solubility of the CUR-HP-ß-CD was 63.5, 60.1, and 52.9 times that of the unformulated curcumin in H2O, HCl (pH 1.2), and PBS (pH 6.8), respectively. The bioavailability of CUR-HP-ß-CD is improved 2.8 times and 38.7 folds higher brain concentrations. Moreover, the therapeutic anti-epileptic effects of CUR-HP-ß-CD were much more effective in pentylenetetrazol (PTZ)-induced zebrafish and mouse models.This study showed a simple and reproducible strategy to effectively improve the bioavailability and therapeutic effects of curcumin, which could be potentially used in epilepsy treatment.


Assuntos
Curcumina , Epilepsia , Animais , Camundongos , 2-Hidroxipropil-beta-Ciclodextrina , Curcumina/farmacologia , Peixe-Zebra , Epilepsia/tratamento farmacológico
18.
Front Plant Sci ; 13: 1006409, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36110359

RESUMO

Cytokinin is an important endogenous hormone in plants performing a wide spectrum of biological roles. The type-A response regulators (RRAs) are primary cytokinin response genes, which are important components of the cytokinin signaling pathway and are involved in the regulation of plant growth and development. By analysis of the whole genome sequence of wheat, we identified 20 genes encoding RRAs which were clustered into eight homologous groups. The gene structure, conserved motifs, chromosomal location, and cis-acting regulatory elements of the TaRRAs were analyzed. Quantitative real-time polymerase chain reaction (qRT-PCR) results showed that the expression levels of most of the TaRRAs increased rapidly on exogenous cytokinin application. Moreover, the TaRRA family members displayed different expression profiles under the stress treatments of drought, salt, cold, and heat. This study provides valuable insights into the RRA gene family in wheat and promotes the potential application of these genes in wheat genetic improvement.

19.
Sci Transl Med ; 14(658): eabq4130, 2022 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-35976993

RESUMO

Despite the remarkable efficacy of COVID-19 vaccines, waning immunity and the emergence of SARS-CoV-2 variants such as Omicron represents a global health challenge. Here, we present data from a study in nonhuman primates demonstrating durable protection against the Omicron BA.1 variant induced by a subunit SARS-CoV-2 vaccine comprising the receptor binding domain of the ancestral strain (RBD-Wu) on the I53-50 nanoparticle adjuvanted with AS03, which was recently authorized for use in individuals 18 years or older. Vaccination induced neutralizing antibody (nAb) titers that were maintained at high concentrations for at least 1 year after two doses, with a pseudovirus nAb geometric mean titer (GMT) of 1978 and a live virus nAb GMT of 1331 against the ancestral strain but not against the Omicron BA.1 variant. However, a booster dose at 6 to 12 months with RBD-Wu or RBD-ß (RBD from the Beta variant) displayed on I53-50 elicited high neutralizing titers against the ancestral and Omicron variants. In addition, we observed persistent neutralization titers against a panel of sarbecoviruses, including SARS-CoV. Furthermore, there were substantial and persistent memory T and B cell responses reactive to Beta and Omicron variants. Vaccination resulted in protection against Omicron infection in the lung and suppression of viral burden in the nares at 6 weeks after the final booster immunization. Even at 6 months after vaccination, we observed protection in the lung and rapid control of virus in the nares. These results highlight the durable and cross-protective immunity elicited by the AS03-adjuvanted RBD-I53-50 nanoparticle vaccine.


Assuntos
COVID-19 , Vacinas Virais , Adjuvantes Imunológicos/farmacologia , Animais , Anticorpos Neutralizantes , Anticorpos Antivirais , COVID-19/prevenção & controle , Vacinas contra COVID-19 , Humanos , SARS-CoV-2 , Vacinas de Subunidades
20.
Plant Biotechnol J ; 20(8): 1606-1621, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35514029

RESUMO

Genetically enhancing drought tolerance and nutrient use efficacy enables sustainable and stable wheat production in drought-prone areas exposed to water shortages and low soil fertility, due to global warming and declining natural resources. In this study, wheat plants, exhibiting improved drought tolerance and N-use efficacy, were developed by introducing GmTDN1, a gene encoding a DREB-like transcription factor, into two modern winter wheat varieties, cv Shi4185 and Jimai22. Overexpressing GmTDN1 in wheat resulted in significantly improved drought and low-N tolerance under drought and N-deficient conditions in the greenhouse. Field trials conducted at three different locations over a period of 2-3 consecutive years showed that both Shi4185 and Jimai22 GmTDN1 transgenic lines were agronomically superior to wild-type plants, and produced significantly higher yields under both drought and N-deficient conditions. No yield penalties were observed in these transgenic lines under normal well irrigation conditions. Overexpressing GmTDN1 enhanced photosynthetic and osmotic adjustment capacity, antioxidant metabolism, and root mass of wheat plants, compared to those of wild-type plants, by orchestrating the expression of a set of drought stress-related genes as well as the nitrate transporter, NRT2.5. Furthermore, transgenic wheat with overexpressed NRT2.5 can improve drought tolerance and nitrogen (N) absorption, suggesting that improving N absorption in GmTDN1 transgenic wheat may contribute to drought tolerance. These findings may lead to the development of new methodologies with the capacity to simultaneously improve drought tolerance and N-use efficacy in cereal crops to ensure sustainable agriculture and global food security.


Assuntos
Secas , Triticum , Regulação da Expressão Gênica de Plantas , Fotossíntese , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Estresse Fisiológico/genética , Fatores de Transcrição/genética , Triticum/genética , Triticum/metabolismo
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